We fine-tune a GPT-2 model [1]} on our dialogs. GPT-2 can generate impressively realistic text, and can be fine-tuned to adapt it to a range of tasks, including dialog system [2]}.We use the default parameters and fine-tune from the pre-trained gpt2 model provided in the HuggingFace transformers library [3]}. This model has approximately 124 million parameters. Running on a single Nvidia Tesla P100 GPU this model averages 0.4 seconds per call, which corresponds to one agent API call or utterance. We fine-tune this model for 10 epochs on our training set, and select the model checkpoint with the highest click-level prediction accuracy on our validation set.
